Flood Origins

So the Forerunners killed off and banished the surviving Precursors, bad move on their part but they don't know it yet. They did it cuz they're greedy and wanted the mantle of responsibility that the humans were originally going to get. The mantle of responsibility says they will try to preserve all life. But some odd years later ancient humans found a space pod, of sorts, filled with powder. The ancient humans were like lets see what this stuff does and gave it to an animal, called Pheru. This animal was a delicacy and eating it meant you were successful or something of the sorts. The powder made them grow at faster rate and they were eating it and thought everything was going just fine. Well one day their favorite little animals started growing tentacles and other mutations and then they started thinking something might be wrong. Well they were totally right, the flood came as the scourge of many human controlled planets. The flood are essentially super-zombies, The Walking Dead zombies have nothing on these guys.  The flood opened up a life time supply of cans whoop-a$$ until the humans found a cure for it. At the same time they were expanding into Forerunner controlled space but that war is for the next post. Read about it with better detail (and less love) here: http://halo.wikia.com/wiki/Flood

Pheru ^